Once the prawns have been washed and cleaned, heat up the grill or griddle. Meanwhile, prepare the dressing in a small bowl with oil, lemon juice, chopped fresh parsley, salt and garlic. When the griddle is hot, cook the prawns, turning them every 3 minutes or so. While cooking, pour the dressing over them to flavour them; this way, they will cook together with the dressing, which will not be wasted but added as you go along.
You can serve them as they are or pair them with a delicious tomato sauce, reduced in a pan and cooked with parsley and garlic to taste.
Plate up and serve hot.